The invention provides an apparatus, system, and method employing a marker based on a membrane that is reflective of ultrasonic waves. The technique allows controlling the resonance frequency of the membrane, amplitude, non-linearity and reverberation period by modifying material properties and geometrical properties (membrane area and thickness) such that the marker appears prominently on ultrasound imaging. The marker can be tailored for use either in color Doppler mode or harmonics mode.
